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	<div id="winchm_template_title">!lookaside</div>
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	<div id="winchm_template_content"><div id="mainSection"><p>The <b>!lookaside</b> extension displays information about look-aside lists, resets the counters of look-aside lists, or modifies the depth of a look-aside list.</p>
<pre class="syntax"><b>!lookaside [</b><i>Address</i><b> [</b><i>Options</i><b> [</b><i>Depth</i><b>]]]</b>
<b>!lookaside [-all]</b>
<b>!lookaside 0 [-all]</b></pre>
<h2><a id="ddk__lookaside_dbg"></a><a id="DDK__LOOKASIDE_DBG"></a>Parameters</h2>
<p></p>
<dl>
<dt><a id="_______Address______"></a><a id="_______address______"></a><a id="_______ADDRESS______"></a>       <i>Address</i>      </dt>
<dd>
<p>Specifies the hexadecimal address of a look-aside list to be displayed or modified.</p>
<p>If <i>Address</i> is omitted (or 0) and the <b>-all</b> option is not specified, a set of well-known, standard system look-aside lists is displayed. The set of lists is not exhaustive; that is, it does not include all system look-aside lists. Also, the set does not include custom look-aside lists that were created by calls to <b>ExInitializePagedLookasideList</b> or <b>ExInitializeNPagedLookasideList</b>.</p>
<p>If <i>Address</i> is omitted (or 0) and the <b>-all</b> option is specified, all look-aside lists are displayed.</p>
</dd>
<dt><a id="_______Options______"></a><a id="_______options______"></a><a id="_______OPTIONS______"></a>       <i>Options</i>      </dt>
<dd>
<p>Controls what operation will be taken. The following possible <i>Options</i> are supported. The default is zero:</p>
<p></p>
<dl>
<dt><a id="0"></a>0</dt>
<dd>
<p>Displays information about the specified look-aside list or lists.</p>
</dd>
<dt><a id="1"></a>1</dt>
<dd>
<p>Resets the counters of the specified look-aside list. </p>
</dd>
<dt><a id="2"></a>2</dt>
<dd>
<p>Modifies the depth of the specified look-aside list. This option can only be used if <i>Address</i> is nonzero.</p>
</dd>
</dl>
</dd>
<dt><a id="_______Depth______"></a><a id="_______depth______"></a><a id="_______DEPTH______"></a>       <i>Depth</i>      </dt>
<dd>
<p>Specifies the new maximum depth of the specified look-aside list. This parameter is permitted only if <i>Address</i> is nonzero and <i>Options</i> is equal to 2. </p>
</dd>
</dl>
<h3><a id="Additional_Information"></a><a id="additional_information"></a><a id="ADDITIONAL_INFORMATION"></a>Additional Information</h3>
<p>For information about look-aside lists, see the 
       <a href="http://go.microsoft.com/fwlink/p/?linkid=201141">Windows Driver Kit (WDK) documentation</a> 
       and <i>Microsoft Windows Internals</i>, by Mark Russinovich and David Solomon. (These 
       resources may not be available in some languages and countries.)</p>
<h2>Remarks</h2>
<p>Look-aside lists are multiprocessor-safe mechanisms for managing pools of fixed-size entries from either paged or nonpaged memory.</p>
<p>Look-aside lists are efficient, because the routines do not use spin locks on most platforms.</p>
<p>Note that if the current depth of a look-aside list exceeds the maximum depth of that list, then freeing a structure associated with that list will result in freeing it into pool memory, rather than list memory. </p>
<p>Here is an example of the output from this extension:</p>
<pre class="syntax" xml:space="preserve"><code>!lookaside 0xfffff88001294f80

Lookaside "" @ 0xfffff88001294f80  Tag(hex): 0x7366744e "Ntfs"
    Type           =       0011  PagedPool RaiseIfAllocationFailure
    Current Depth  =          0  Max Depth  =          4
    Size           =        496  Max Alloc  =       1984
    AllocateMisses =          8  FreeMisses =          0
    TotalAllocates =     272492  TotalFrees =     272488
    Hit Rate       =         99% Hit Rate   =        100%
</code></pre>
<h2>Requirements</h2>
<table>
<tr>
<th width="30%">
<p>DLL</p>
</th>
<td width="70%">
<dl>
<dt>Kdexts.dll</dt></dl></td></tr></table></div></div>	
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